fool

Concise Oxford English Dictionary © 2008 Oxford University Press:
fool1

▶noun

• 1 a person who acts unwisely.

  ■ archaic a person who is duped or imposed on.

• 2 historical a jester or clown, especially one retained in a royal or noble household.

▶verb

• 1 trick, deceive, or dupe.

• 2 (usu. fool about/around) act in a joking or frivolous way.

  ■ (fool around) chiefly N. Amer. engage in casual or extramarital sex.

▶adjective N. Amer. informal foolish or silly.

– phrases
be no (or nobody's) fool be shrewd or prudent.
make a fool of trick or deceive (someone) so that they look foolish.

■ (make a fool of oneself) appear foolish through incompetent or inappropriate behaviour.

more fool —— the specified person is behaving unwisely.

– derivatives
foolery noun.

– origin ME: from OFr. fol ‘fool, foolish’, from L. follis ‘bellows, windbag’, by extension ‘empty-headed person’.

Concise Oxford English Dictionary © 2008 Oxford University Press:
fool2

▶noun chiefly Brit. a cold dessert made of puréed fruit mixed or served with cream or custard.

– origin C16: perh. from fool1.